Whenever I first hooked up my thermostat (which required the c-wire adapter) the AC compressor would turn on whenever the heat turned on. I was able to locate the wire that controlled the ac compressor and disconnected it since it was/is winter here and AC was not critical. Now the weather is starting to turn and I need to get the AC working. The blue wire on the right in the attached photo is what I disconnected. Everything was hooked up exactly as it was before
Is your Hvac system a conventional or o/b (heat pump) ?
Because I made the mistake of thinking my system was convention and it was actually O/B (heat pump). It was causing the same thing to happen - wanted the heat, ac would pop on, wanted it colder it turned the heat on.
My solve was the wire I labeled as W was actually an O/B - my Honeywell unit made it look like it was W, go figure.
This video helped me solve this mix up.
Pretty sure it’s a conventional gas furnace. Before the Wyze Thermostat the AC would not come in when the heat ran. Just the gas furnace and the air handler.
do u have only 1 wire per terminal on the C wire adapter? Only 1 wire should be on each terminal on the adapter…post more pix
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Your Y wire that goes to the outside unit is likely plugged into the wyze adapter, not into the Y terminal on your furnace, Show a wider image, including the adapter and the actual thermostat wire bundles
I’m having the same issue
stick with your 1 thread, trying to reply to you in multiple places isn’t going to help.
The AC compressor needs to be directly connected to the furnace board, not to the C adapter.
Take the white wire out of this wirenut and run an additional wire inside the furnace to it that goes to Y on the furnace. Reattach the light blue wire to C on your furnace.
Leave the humidifier where it is, didn’t need to draw it in.
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Thanks speadie. That did the trick.
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Hello speadie. Hoping that you can help me out again on a similar issue. I just had a new HVAC system installed, but kept the existing thermostat wiring in place from the the Wyze thermostat to the unit in the basement because it snakes through walls and finished ceilings and was going to be too difficult to replace. I couldn’t figure out how to get the wiring correct when the tech was here yesterday so i got a cheap “dump” thermostat from Home Depot so the tech could finish installing the unit and get it working.
I tried hooking it up the same way as before but when turned it on and triggered the fan without calling for cooling, the compressor outside still turned on. There is another module in the wiring that i think is changing things. He installed a shut off value in the drain line so it if backs up, the unit turns off.
I took your original sketch that got me working 4 years ago and tried to diagram the wiring as i think it should be. I’ve included also marked up photos of the current working setup with he dumb thermostat. Quick note, that the dark blue wire from the thermostat with the yellow electrical tape goes to the “Y” on the thermostat as that is how is was connected to the original thermostat before i hooked up the Wyze in 2021.
when you tried hooking it up the old way, did you reset the thermostat and make sure to tell it that your old thermostat had the following wires: Rc, G, Y, W ? You will still need the C adapter, and if you tell it that you have a C wire, it will not set up the thermostat to use the C adapter.
Yes. This was the setup it instructed me to do
The thing that is throwing me a bit is the drain shut I’m off wiring. It makes sense to me that it would go between the thermostat yellow and the adapter yellow. That way if the float is triggered it intercuts the signal to the control panel and turns off the AC unit.
The float is interrupting the A/C Y wire.
The C adapter needs to go in the splice location, not on the furnace circuit board.
if you share clear images of the splice location i can make a color coded diagram for you to follow.